Sea level rise threatens the North Sea coast more than expected

https://phys.org/news/2025-11-sea-threatens-north-coast.html

As a result of climate change, rising sea levels are threatening low-lying coastal areas around the world, such as the Wadden Sea in the North Sea. Tidal basins form a natural protective barrier there. They connect the mainland with the offshore islands. They fill with seawater during high tide and empty again during low tide. Sediments are deposited in the process, causing the seabed to rise steadily.
In this way, the basins compensate for rising sea levels. This ability to adjust has recently declined significantly however. Sea levels are rising faster than the bottom of the tidal basins. This is what researchers at the Hereon Institute for Coastal Systems—Analysis and Modeling have found in their latest study, published in Communications Earth & Environment.

The researchers also found that the height growth of tidal basins had been incorrectly estimated in the past. They evaluated data sets on water depth and seabed topography that had been measured over the years using a wide variety of methods and instruments. The result: small-scale structures such as tidal creeks and channels were often inadequately recorded. "This repeatedly led to distortions in earlier studies," says Zhang.

Sediment accumulation in the tidal zone was often overestimated, while erosion in deeper areas was underestimated. The researchers cleaned up the data sets and corrected previous estimates. "Our study paints a much clearer and more worrying picture than previously assumed in science. It follows that current and future measures in coastal protection and climate adaptation must be significantly more comprehensive and ambitious."